Was that really a quake?

October 3, 2012

If an earthquake happens in western North Dakota and no one notices, did it really happen?

Yes, according to geologists.

Officials with the N.D. Department of Mineral Resources and the Earthquake Studies Office at the Montana Bureau of Mines and Geology said the 3.3 magnitude earthquake was centered 11 miles southeast of Williston last Friday morning. The only instrumentally located quake in the state happened July 8, 1968, near Bismarck, although shocks have been felt from quakes occurring in other locations, including Canada, Iowa, Minnesota, Montana and Nebraska.

Sensing the chance for a good conspiracy theory, some may speculate that the quake could have been caused by hydraulic fracturing taking place in western North Dakota's booming oil patch. Geology experts quickly shot down that theory, noting that Friday's small quake would have happened at about 2,000 feet below the surface, too shallow to be caused by the fracking taking place much deeper in the ground. There is no proven link between fracking and earthquakes, they said.

It was still a noteworthy experience, given the rarity of noticeable quakes in North Dakota. Officials said someone nearby the quake's center could have noticed the ground move a bit, but it's unlikely given the quake's location. We're glad the state is unlikely to experience any large, damaging earthquakes, and that even small quakes are rare, but it's certainly an interesting footnote to the state's geologic history.